I have this VB.NET console application which will generate PDF by calling SSRS reports but this is failing in line reportDefinition = RS.GetItemDefinition(reportName). Can someone help?

Imports SSRS_TO_PDF.ReportingServiceWebReference
Imports System.IO
Imports System.Web.Services.Protocols

Module Module1

    Sub Main()
        Dim RS As New ReportingServiceWebReference.ReportingService2010
        Dim ex As New ReportingService2010
        RS.Credentials = System.Net.CredentialCache.DefaultCredentials
    

        'RS.Credentials = System.Net.CredentialCache.DefaultCredentials

        Dim reportName As String = "http://192.168.108.23/Reports/Pages/Report.aspx?ItemPath=%2fGROW%2fUser_Tb_Server_Check"
        Dim reportDefinition As Byte() = Nothing
        Dim doc As New System.Xml.XmlDocument

        Try
            reportDefinition = RS.GetItemDefinition(reportName)
            Dim stream As New MemoryStream(reportDefinition)
            'write to pdf file
            Dim file As New FileStream("C:\Temp\TestReport3.PDF", FileMode.Create, FileAccess.Write)
            stream.WriteTo(file)
            file.Close()
            stream.Close()

        Catch e As SoapException
            Console.WriteLine(e.Detail.InnerXml.ToString())
            MsgBox(e.ToString)
        Catch e As IOException
            Console.WriteLine(e.Message)
        End Try

    End Sub

End Module